Lost without a clue: Saltwater in oil

[Crusty Joker]

Admiral,
You are on top of the items I would check...
Temp alarm function and a cooling water pressure alarm for emergency might be a good idea for reminder for commercial crew.
Along with a check list for engine operation...
use a fail safe check list to operate engine.
I have worked on these engines before. One was seized and rusted up
with sea water left in engine for 3 weeks. We eventually got it to free up
and turn over. Then did the in situ remedies changed the head gasket etc.
Head gasket kit is tricky... if I remember correctly. That engine took days of tapping to get penetrants to free the rings. And turn over...
I had to do it 2X to get it right. There is a rubber / neoprene
insert somewhere that has to be there. That was a very long time ago. That engine survived and ran well without rebuild as I would have had to cut it out of the boat. That one was built like a Jaguar. Place engine on 2 small bricks above the cobblestone floor and assemble automobile around it... do not allow crew to smoke ganga or drink...
Keep me posted on your success here.
In your area of the world, I prefer either Perkins or Yanmar.
Not a bad engine you have just not modern. Modern engines need to leave all the digital stuff off and stay with mechanical and analog... Hate Smith Instruments... but you live with what you have. Nice size boat. Stay well. Uncle b

[Jack C]

My Perkins 4236 has to my surprise a raw water cooled oil heat exchanger and a raw water cooled gearbox. Perhaps your engine has one of these as well? A leak in the raw water to oil heat exchanger would introduce sea water into the oil. Just a thought.

[Mike Banks]

Does your vessel start immediately or does it turn over for a few seconds before firing up? Are you using an electric raw water pump connected to the engine key switch as a primer or main pump?

It sounds to me as though the only way for saltwater to enter your engine if there is no leaks in the block or the heat exchanger is from the water-cooled exhaust system. Some systems have a rising pipe to stop waves washing back up into the exhaust system when the engine is not running. They are a mixed blessing, because such a system can allow sea water to back up into cylinders and cause trouble from the water going into the exhaust pipe elbow.
.

[BruceS]

https://www.gumtree.com.au/s-ad/murr...ne-/1245900545


He had 2 of 'em complete with controls, cables & Hamilton jet.

[Michael Pope]

This may not be pertinent but! I used to lve right here in vancouver and some of my customers (Clients would do the Vic -Maui Race or trans pac ) .
Come back by going north and get lotsa wind on fairly broad reach. Go Fast for hours and hours . Have nice practical water lift mufflers back by the transom. No way for water to get in--- Oh Yeah! Some of these boats would be going Hull speed plus for days and the Quarter wave height would be almost Lifeline height 30 inches above deck 34 to 36 above top of water-lift.
Would get tons of water in oil while charging batteries to keep beer cold and forget how badly they did in the race!! Ha
Annother friend gotso pissed at fixing these guys that when he built his cruiser he put the exhaust all the way up the rather short Mizzen Mast.
Corroded the mast right out fell down on the deck in less than a year.
The ocean is not your friend it will outsmart you always !! Mike Pope

[a64pilot]

Pretty sure he said it was a belt driven raw water pump

[mvweebles]

Either an oil cooler (transmission, hydraulic, other) or exhaust. Check age of exhaust elbow and check that the raw water injection point is well below the top of the elbow. If your elbow is jacketed, also an excellent candidate for leak.

Exhaust elbows are definitely a service item. Cast iron barely last for a few years an a couple hundred hours. Stainless can last 500 hours or more if properly fabricate of a quality alloy.

[mlydon]

I had the same issue with a westerbeke w30. That engine has a separate oil cooler, fed from the raw water pump, on the starboard side of the engine, the output of which then travels´ round back to enter the rear of the exhaust heat exchanger.
At runtime, oil under pressure entered the water side, leaving a slick you coulld see in the exhaust output. Once shut down, the water would enter the oil side, putting salt water into the oil.
The oil pulled from the engine looked like an Oreo cookie milkshake.

Get that out of your engine right away, and flush a couple of oil changes through the system ASAP with the raw water OFF. And replace your oil cooler.....

Matt

[mvweebles]

Originally Posted by mlydon

I had the same issue with a westerbeke w30. That engine has a separate oil cooler, fed from the raw water pump, on the starboard side of the engine, the output of which then travels´ round back to enter the rear of the exhaust heat exchanger.
At runtime, oil under pressure entered the water side, leaving a slick you coulld see in the exhaust output. Once shut down, the water would enter the oil side, putting salt water into the oil.
The oil pulled from the engine looked like an Oreo cookie milkshake.

Get that out of your engine right away, and flush a couple of oil changes through the system ASAP with the raw water OFF. And replace your oil cooler.....

Matt

Unless a specialized OEM version, inline oil coolers are relatively cheap. I just replaced one for about $130. Mine was a hydraulic cooler - cost of oil was almost more than the cooler.

Both the exhaust elbow and Inline oil coolers are wear items and should be replaced at regular intervals. 5-10 years depending on construction and use

[mvweebles]

Also, and don't mean to scare you, but if you've noticed more steam in exhaust and harder starting, could be a head gasket. Once you've ruled out other stuff, you could crack each injector while running and see if the RPMs decline uniformly. If a cylinder dies, usually the back one due to heat. But I'd check the exhaust elbow and coolers (if equipped) first.

[pbmaise]

Originally Posted by SVHarmonie

I have nothing definative, just some ideas, and need some more information...I know some of these questions will seem annoying, but these are the kinds of things I would look for if I was there:

When you say "in the engine" I assume you mean in the oil. Is there evidence of water anywhere else? Is there enough water to measurably raise the oil level?

After an oil change how quickly does water appear?

You say your exhaust elbow is "above the water line," How high? and is there an additional loop in the exhaust line above that? Is there a syphon break anywhere in the system? Does the exhaust line dip below the water line anywhere at all? How old is the exhaust elbow? When was the last time it was removed?

Does the exhaust leave the hull out the side, out the back?

I assume you have a water lock muffler. Have you looked to see if it is full?

How much sailing is done compared to motoring? Water making its way back into the exhaust while the engine is running is ALMOST impossible.

Are you still loosing coolant? Can you pressure test the coolant system? The taste test isn't always definitive... Don't assume the head gasket is the only place for coolant to disappear. There are usually gaskets in the exhaust manifold jacket that separate coolant from exhaust that can fail too...

Thank you for your diagnostic help everyone.

I have come back to my vessel after the commercial team operated the vessel on their own for several months. Getting valid information and wondering if you are being told the full story is difficult.

My engine has always suffered some minor coolant loss and I do know one of the hoses that was not changed last year has been replaced recently. I was shown the old hose and it was apparent that it burst. Therefore, YES, I do suspect that the engine overheated after the burst hose event.

Yes when I say in the engine I mean in the oil and water is accumulating in the oil pan. Enough that the oil level rises and we can draw out a water sample from below the oil. The mechanic did the taste test on the saltwater removed from the oil pan. I will be going to the boat shortly to examine myself, however, am pretty confident he is telling the truth.

The head gasket kit contains way more parts than just a head gasket. This is very interesting for me to see. I have not heard of possible coolant loss directly into the exhaust before. However, now that I see all these other gaskets it makes sense to me. Therefore, it is making sense to me to take the whole engine apart to solve the slow coolant loss since if that is a gasket it will only get worse over time.

In other words, I am concluding there are multiple issues I am dealing with..

#1 The slow coolant loss
#2 The consequence of what may have been an overheating event
#3 The saltwater in the oil pan (BTW yes oil looks milky and I am now thinking of buying a new oil pan because having saltwater in the oil pan will rust it out fairly quickly.)

Good idea on testing oil and coolant. I will look for testing kits or place that can test.

Saltwater appeared in the oil within a week of last oil change.

The commercial operation is now almost 100% engine on and the foresail is just really for tourists to take pictures. Heeling is almost zero and I certainly am not flying a hull. Further, I am in Langkawi bay with almost zero waves on a wide trimaran. Therefore, I am thinking the only path for saltwater back in is back flow from the very tall exhaust loop. Which brings up an idea. There really isn't a big need for such a tall riser loop. Without any high seas here that could be safely reduced.

"I assume you have a water lock muffler. Have you looked to see if it is full?"

Can someone explain this question to me. Are you suggesting I take it apart and look inside. It is a large stainless steel anode protected round tank. Is it possible that after 20 years this tank is full of junk?

Exhaust exits out the side roughly a few inches above waterline.

"You say your exhaust elbow is "above the water line," How high? and is there an additional loop in the exhaust line above that? Is there a syphon break anywhere in the system? Does the exhaust line dip below the water line anywhere at all? How old is the exhaust elbow? When was the last time it was removed?"

Exhaust elbow is the term I am using for the point the seawater is injected into the exhaust. It is now 20 years old and has never been removed. It is about 4 inches above water line and has never been removed. I have seen the local welding shop making a new one for a different vessel and admit I wondered why.

From the injection point the exhaust line drops down to the base of the exhaust tank. At this point it is below the waterline. I have heard the term siphon break, however, I do not have one. I do not believe it is possible for a siphon to occur in the water I am in now.

I will look closely today at how high the exhaust is above the waterline.

[pbmaise]

Originally Posted by mvweebles

Unless a specialized OEM version, inline oil coolers are relatively cheap. I just replaced one for about $130. Mine was a hydraulic cooler - cost of oil was almost more than the cooler.

Both the exhaust elbow and Inline oil coolers are wear items and should be replaced at regular intervals. 5-10 years depending on construction and use

Oil cooler is cooled by the freshwater loop. We already pulled off oil cooler and checked.

[pbmaise]

Originally Posted by mvweebles

Either an oil cooler (transmission, hydraulic, other) or exhaust. Check age of exhaust elbow and check that the raw water injection point is well below the top of the elbow. If your elbow is jacketed, also an excellent candidate for leak.

Exhaust elbows are definitely a service item. Cast iron barely last for a few years an a couple hundred hours. Stainless can last 500 hours or more if properly fabricate of a quality alloy.

Stainless and I suspect it was an expensive grade of stainless. I am well past 500 hours. At least several times over.

[SVHarmonie]

Originally Posted by pbmaise

Exhaust elbow is the term I am using for the point the seawater is injected into the exhaust. It is now 20 years old and has never been removed. It is about 4 inches above water line and has never been removed. I have seen the local welding shop making a new one for a different vessel and admit I wondered why.

From the injection point the exhaust line drops down to the base of the exhaust tank. At this point it is below the waterline. I have heard the term siphon break, however, I do not have one. I do not believe it is possible for a siphon to occur in the water I am in now.

If your exhaust elbow is only 4" above the water line, not having a syphon break is a serious flaw.

Read this for more than you ever wanted to know about exhaust system design: https://www.sbmar.com/articles/desig...xhaust-system/

[gpeacock]

We had this problem a few years ago where our anti-siphon for the raw water line that injects into the exhaust elbow had failed. Funnily enough it had probably failed for a long time but we only noticed it when we were up a tidal river. At low tide the fresh water change was enough to drop the exhaust elbow injection point below the water line and allow the water to siphon. It was very difficult to diagnose because at high tide the salt water content was enough to have it not happen.

Once we did sort out the issue I removed the anti-siphon valve and attached a small hose that now runs up to my cockpit drain. I will never have a different system again. Having the hose is fool proof, nothing can fail and as an added bonus you can hear the water dribbling out the hose which tells you that there is raw water flow. Win Win.